originally posted by mjlavelle
i am guessing that this is related to the cooling system thread from last week. And i see goingnuts has chimed in with his "quite long" trips of 150 miles in on a "very warm" day in england, which i am guessing was about 80 degrees. The fact that his temperature gage stayed in the normal range is supposed to support the fact that his cooling system is in perfect condition. I did not have the heart to tell him that most cars will do the same thing right up to the point that the expansion tank blows up. It is usually not something that is progressive, like the car running warmer and warmer before a failure. Mine was running perfectly cool, right up to, and even after the cloud of steam came out from under my hood, when my expansion tank failed.
As far as preventative maintenance, the most common thing is the cooling system. And it will fail suddenly, and in a major way. So, replacing it after 80 to 100k miles is not unreasonable. And if you are already replacing one part, why not replace the hoses, the pump (which was a bad design, until about 2002 or so). It also makes sense to replace all of the sensors as well, at the same time. The high temp plastics used in the expansion tank and the hose connections and the water pump impeller will degrade over time, and fail. So, it is a good bet that if one part of the system fails, then the others are not far behind. The same thing applies to the vacuum hoses and intake boots. Other parts are debatable. I would not replace sensors just to replace them. But, if you are replacing your belts, then doing the pulleys, tensioners, and fan clutch just seems to make sense, since you are already in there. It also makes sense to me to go ahead and replace any sensors that you can get at with the other parts removed. I think this is part of the disconnect here. A lot of us will replace parts that are difficult to reach, if we have already removed all of the parts necessary to reach them. To me, it makes sense, on a high milage car. But this is also tied to your budget. If you can't afford to do this, then just repair the parts that failed. But, you will have to live with the knowledge that something buried deep inside of those parts you replaced may (and in my experience will) fail, and you will have to go back in again. That is what is at the core of a lot of the advice that you see on this forum. The problem is that not everyone is so diplomatic about handing out this advice, and will just call you an idiot for not replacing everything. I don't know if this is just frustration from giving out the same advice for years, and not realizing that some people are new to all of this, or if they are just a$$holes in general. Probably both.
There is nothing wrong with waiting for something to fail, and only fixing the part that fails. Most of what you read about doing everything at once is just the voice of experience. It is just not delivered well.
Of course, as with anything else, there are the fanatics, or just overly cautious people, who will replace parts simply because they can afford to, and it makes them feel better. That is why you should read as much as you can on a particular subject, and filter out the extremes.
I, for one, do believe that replacing the entire cooling system is reasonable, especially when you experience a failure of one of the items, or after you hit the 80k mile mark. Especially if you have a 1999 - 2002 model, with the poorly designed water pump and expansion tank. But, not replacing items that are part of the regular maintenance schedule, and waiting for them to fail, is just asking for trouble.